It is known to form a cross-sectional profile of a tubular member by a hydroforming process in which a fluid filled tubular member is placed within a cavity of a die and then the die is closed so that the tubular member is pinched within the die. Fluid pressure is then increased inside the tubular member to expand the tubular member outwardly against the cavity of the die to provide a tubular member having a die formed cross-sectional profile.
After preliminary shaping in the hydroforming die, the tubular member is removed from the die for further machining, processing, or fabricating. The tubular member is trimmed to have a desired length in a separate shearing operation. The length is established by laser cutting, plasma cutting, or mechanical shearing outside of the hydroforming die. These operations employ additional fixtures to accomplish the machining, processing, or fabrication. The operation also requires additional handling of the tubular member for transportation from the hydroforming die to the shearing equipment. Both of these added requirements increase the manufacturing cost and time. Unless the forming and the shearing operations are equal in length of time, more expense is incurred. If the shearing operation is slower, the tubular members must be inventoried or the hydroforming die will have down time. If the forming process is slower, the shearing apparatus will have down time.
An example of a method and apparatus for hydrotrimming and hydroshearing is disclosed in U.S. Pat. No. 5,941,112 to Ghiran et al. In this patent, a tubular member is manufactured in a hydroforming and hydroshearing apparatus. A substantially right circular cylindrical workpiece is placed in a die and pressurized to hydroform a substantially rectangular tubular product. The workpiece is presheared during a pressurization period and is fully sheared during a withdrawal of a plurality of plunger members while internal pressure is maintained. The plunger members are positioned in the die by respective power cylinders which control the withdrawal thereof.
However, it is desirable to provide a new apparatus and method for hydrotrimming and hydroshearing a tubular member during the hydroforming process. It is also desirable to provide an apparatus and method that eliminates post-forming secondary operation of mechanically shearing or laser cutting the end(s) of tubular members. It is further desirable to provide an apparatus and method having wear parts that are disposable and easy to replace. Therefore, there is a need in the art to provide a new apparatus and method for hydrotrimming and hydroshearing for a hydroforming die that meets at least one of these desires.